翼型绕流分离的微楔控制

MICRO-RAMP CONTROL OF THE BOUNDARY SEPARATION INDUCED BY THE FLOW PAST AN AIRFOIL

基于大涡模拟(LES,Large Eddy Simulation),结合3阶WENO(Weighted Essentially Non-Oscillatory)格式与沉浸边界法(IBM,Immersed Boundary Method),对NACA0012翼型在来流马赫数为Ma=0.5以及10°攻角下,有无微型三角楔涡流发生器作用的三维绕流进行了数值模拟,对比了两者的流场结构变化。数值结果表明,微楔能显著改变翼型绕流的尾涡结构,并能缩小其表面边界层的分离,提高升力,并对微型三角楔涡流发生器的流体分离抑制机理进行了讨论。

Based on the large eddy simulation(LES) and combined with three-order WENO scheme and the immersed boundary method(IBM),the flows past a NACA0012 airfoil with and without a micro-ramp vortex generator have been simulated at the Mach number of Ma=0.5 and in an angle of attack α=10°,and different flow structures under these two cases have been compared.Our numerical results show that the micro-ramp can change wake structures,and can lead to the reduction of a boundary layer separation area,and an increase of lift.Furthermore,the suppression mechanism of the micro ramp on flow separation have been discussed.